Re: Acceptance Testing, your view is correct. Those 'specs' can be provided in a machine format (image, HTMLDom, etc) to be compared to the output from the test run. :). Reading some of the other comments I agree 'Acceptance Testing' covers a wide swath. Maybe break out Security, Compliance, etc. I have no idea what they would be called though. :S

Re: Perf. Testing, Unit tests can pass, integrations pass, but the running application does not respond before a timeout; but maybe does in 120 seconds. A trick I learned was that Chrome can throttle the network speed of a request. This means headless version can as well :). The other side of Perf. Testing is x successful responses in Y seconds under Z load. The measure of these can be benchmarked using APM tools (Application Process Monitors). New Relic, Sentry, and AppDynamics are three of the more well known vendors.

"Application Testing": as wide as the horizon and as deep as a gravity well of a black hole.